This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This management study treats Yerkes'colonies of SIV-infected and uninfected sooty mangabeys (SMs) as cohorts for a biannual immuno-virological evaluation. The biannual sample collections began in 2004 and between the years of 2004-2007 338 samples were collected. A complete analysis has been conducted on these samples for measurement of viral load and 28 immunological parameters. This information, and the repository of plasma and PBMC frozen samples are made available for selected research projects to both Yerkes and non-Yerkes investigators upon request. We are now in the process of completing the third survey with 90 samples collected to date. The samples utilized from this project have been instrumental to several important publications in the field. This general approach has enabled us to generate a set of immunological and virological data to conduct a systematic longitudinal assessment of the animals'health status, with specific focus on the course of SIV infection. This set of data has also allowed the rapid and effective identification of SMs with specific immunological and/or virological features, and to match against the completed SM colony pedigree.